Portable shelter structure



FIG. 1 is a front elevational view of a portable shelter structure showing my new design,

FIG. 2 is a right-side elevational view thereof, the left-side elevational view being a mirror image and,

FIG. 3 is a top plan view thereof, the bottom plan view being disclaimed; and,

FIG. 4 is a perspective view thereof, the interiors of all vertical pole mask elements being the same as the full view of the left rear mask.

The broken lines of the poles are for illustrative purposes only and form no part of the claimed design. 

I claim the ornamental design for portable shelter structure, as shown and described. 